Variable speed transmission



Nov. 26, 1940. I

F. J. SYWEET 2,223,135

VARIABLE SPEED TRANSMISSION Filed Sept 16, 1938 4 Sheets-Sheet 1 $0,607695 M INVENTOR. v v I v BY 310% d 6W ATTORNEY.

Nov. 26, 1940. F. J. SWEET v 2,223,135

VARIABLE S PEED TRANSMISSION Filed Sept. l6, 1938 4 Sheets-Sheet 2 Now26,

F. J. SWEET 2,223,135

VARIABLE SPEED TRANSMISSION Filed Sept. 16, 1938- 4 Sheets-Sheet 3 43zfiy. 6 73 15 i 14 E k :4: i:56;l

[/ATTORNEY.

Nov. 26, 1940. F. J. SWEET 2,223,135

VARIABLE SPEED TRANSMI S S ION Filed Sept. 16, 1958 4 Sheets-Sheet 4 260JNVENTOR.

v ATTORNEY.

Patentecl'Nov. 26, 1940 UNITED STATES VARIABLE SPEED TRANSMISSION FloydJ. Sweet, Elmira, N. Y.,. assignor to Bendix Aviation Corporation, SouthBend, Ind., a corporation of Delaware Application September 16, 1938-,Serial No. 230,294

9 Claims. (01. 74-290 The present invention relates to variable speedtransmissions and more particularly to variable ratio gearing forvelocipedes and the like, arranged to be incorporated in the wheel hubof the vehicle.

It is an object of the present invention to provide a novel gear unit ofthe above type which is efficient and reliable in operation while beingsimple and economical in construction.

It is another object to provide such a device incorporating gearsconstantly in mesh, with manually shiftable keying means for effectingchanges in gear ratio.

It is a further object to provide such a device 15: in which the keyingmeans are shifted by means of a snap-action device whereby the changesin gear ratio are effected surely, quickly and without lost motion.

It is another object to provide such a device in 20, which the shiftingmeans is small and compact, but easily operated and not subject tosticking or jamming.

It is another object to provide such a device in which the shifting iseiiected by a small angular '25 f motion of a rotary shifter.

'30: in a commercial type of coaster brake.

Further objects and advantages will be apparent from the followingdescription taken in connection with the accompanying drawings in which:

Fig. 1 is a side elevation partly in section and partly broken away of acommercial form of bicycle coaster brake with which is incorporated apreferred form of the present invention;

Fig. 2 is a similar view showing the reduction 40 gearing in shiftedposition;

line 3--3 of Fig. 1 showing the reduction gearing and associated parts;

Fig. 4 is a section taken substantially on the line 44' of Fig. 2showing the shiftable keying means and associated parts;

Fig. 5 is a section taken substantially on the line 55 of Fig. 1 showingone form of operating means for the shift;

Fig. 6 is an end elevation of the device showing another preferred formof shifting means;

Fig. 7 is a view similar to Fig. 1 Showing a modified form of keying andshifting means;

Fig. 8 is a detail of the gearing as illustrated in Fig. 7, showing thekeying means in shifted position;

Fig. 9 is a perspective view of a sub-assembly including a transmissionof the type illustrated in Fig. 1, with the shifting mechanism shown inFig. 6; and

Fig. 3 is a section taken substantially on the Fig. 10 is a detail inperspective showing in disassembled relation the shiftable keys and theoperating mechanism therefor of the transmission illustrated in Fig. 1.

In Fig. 1 of the drawings there is illustrated a cylindrical hub memberI journalled as indicated at 2 on an axle 3 which is adapted to beclamped in conventional manner in the frame of a velocipede such as abicycle, not illustrated. The hub l is arranged to be rotated by anoperating membar 4 journalled at 5 on the axle 3 and supporting theadjacent end of the hub I by means of bearings 6. A driving connectionis provided between the operating member 4 and the hub comprising a nutmember 1 threaded on the operating member and provided with wedges 3adapted to engage a pair of arcuate clutch elements 9 loosely mounted inthe hub and adapted to engage and rotate the same when the nut member Iis actu ated by forward rotation of the operating member.

Braking means for the hub under the control of the operating member 4are provided in the form of a sleeve brake ll arranged to be connectedby a dental clutch element I 2 to a stationary clutch element I3. BrakeSleeve H is adapted to be expanded by the wedges 8 of nut l and Wedgesit of clutch element I2 into frictional engagement with the interior ofthe hub l upon backward rotation of the operating member 4.

It will be appreciated that the structure so far described is thepresent commercial form of the coaster brake illustrated and describedin the patent to Morrow No. 906,149, and since no novelty as'respectsthis structure is herein asserted, further description thereof is deemedunnecessary.

According to the present invention, the operating member t serves as acarrier for a plurality of planetary reduction gears, and for thispurpose is provided with a plurality of bearings 14 for planet gears 15rotatably mounted thereon and meshing with an orbit gear #6 formed inthe interior of a driving sprocket H. A sun gear i8 meshing with theplanet gears is journalled on a bearing member l9 threaded on the axle3.

Means are provided for locking the sun gear 83 to the planet carrier 4,or alternatively to hold the sun gear stationary in order to transmitrotation directly or at a reduced gear ratio respectively, from thesprocket I! to the operating member 4. As illustrated in Figs. 1 to 4, 9and 10, the locking means comprises a plurality of bifurcated keymembers 23 pivotally mounted in a spider 22 (Fig. 10) suitably fixed asby welding on an extension 23 of the sun gear 68. When in the low speedposition as lustrated in Fig. l, the keys 2! are arranged to engage inrecesses 2Q in an anchor member 25 which is held from rotation bysuitable means such as an arm 26 arranged to engage the frame of thevehicle. When the keys 2| are moved into high gear position, they arearranged to engage in openings 21 in the planet carrier 4 as illustratedin Fig. 2.

Means are provided for swinging the keys 2| from one operative positionto the other in the form of a shifter ring 28 (Fig. 10), the innerperiphery of which is arranged to engage between the furcations of thekey members 2|, and the outer periphery of which slidably engages withina cup-shaped flange 29 formed on or suitably afiixed to the anchormember 25. Shifter ring 28 is provided with peripheral lugs 3| formed totraverse inclined slots 32 in the cup 29 whereby relative rotationbetween the ring and cup causes traversal of the ring and consequentlyshifting movement of the key members 2|. Manually operable means forrotating the ring 28 are provided in the form of a sleeve member 33journalled on the cup 29 arranged to be rotated by an arm 34 (Fig. 9)suitably fixed thereto. Sleeve 33 is provided with longitudinal slots 35(Fig. 10) arranged to cooperate with keying elements 36 formed on lugs3| to form a splined connection between the ring 28 and sleeve 33.

The manual means for rotating the sleeve 33 is preferably in the form ofa "snap-action device, one form of which is illustrated in Figs. 6 and9. As there shown, a quadrant flange 38 is fixed in any suitable way tothe anchor member 25, and a lever 31 is pivoted thereto at 38 andprovided with a stud 33 arranged to engage an arcuate slot 4| in thequadrant to guide the lever and limit its oscillation. A sliding link 42is pivoted at 43 to the end of the operating arm 34 and is slidablymounted at its opposite end in a lug 44 formed on the end of the lever31. A compression spring 45 is mounted on the sliding link 42 bearingagainst the pivot 43 and lug 44 so as to tend to maintain these elementsin extended relation. A manually operable link 46 is pivoted to the endof the lever 31 and is connected in any suitable way to any preferredform of operating device conveniently located for manipulation by therider of the vehicle.

It will be appreciated that the reduction gear unit herein disclosed isadapted for use with commercial coaster brakes of the Morrow type bymerely substituting the gear units including the planet carrieroperating member 4 for the conventional sprocket-driven operating memberof the coaster brake. As a matter of convenience, it is desirable thatthe gear unit may be adjusted, merchandized and installed as aself-contained unit, and for this purpose the sun gear, anchor memberand associated parts are retained on the bearing member H! by means of alock nut 41 threaded on the end of the bearing. The bearings 2, 5 and 6are adjusted by rotation of the bearing member IS on the axle 3 as bymeans of a spanner engaging the lock nut 41 or in any other suitablemanner, the adjustment being maintained by suitable means such as a locknut 48 threaded on the axle.

In the operation of this embodiment of the invention, starting with theparts in the positions illustrated in Fig. 1, roation of the sprocketand orbit gear member l1 by the operator in a forward direction causesrotation of the planet gears l5 therein. Sun gear I8 is prevented fromrotation by the engagement of the key members 2| in the recesses 24 inthe anchor member 25 whereby the planets l5 are constrained to planetatearound the sun gear, causing rotation of the planet carrier 4 at reducedspeed, which rotation is transmitted to the hub I through the nut 1 andclutch members 9 in the usual manner. When it is desired to operate inhigh gear, the operator manipulates the link 46 to move the lever 31into the position illustrated in Fig. 6 whereby the spring 45 actuatesthe arm 34 to rotate the sleeve 33 and thereby cause traversal of theshifter ring 28 to move the keys 2| into the position illustrated inFig. 2. The sun gear I8 is thereby locked to the planet carrier 4whereby the sprocket and planetary gearing assembly are caused to rotateas a unit, which rotation is transmitted to the hub I as above setforth. When it is desired to return to the low gear position, the link46 is'manipulated to move the lever 31 to the opposite end of the slot4| in the quadrant 30. As soon as the lever 31 passes beyond its deadcenter position with respect to the. arm 34, the spring 45 becomeseffective to urge the arm 34 into its low gear position where it is thusmaintained by the expansive force of the spring.

It will be understood that the arm 34 may, if desired, be directlyoperated by a manual connection. Such an arrangement is illustrated inFig. 5 in which the arm 34 is shown to be actuated by a manuallyoperable link 48. An expansive spring 50 is preferably connected at itsends to the shaft arm 34 and anchor arm 26 as illustrated, whereby it iseffective to urge the shift arm from any intermediate position towardthe nearest end of its arc of travel.

In the embodiment of the invention illustrated in Figs. '1 and 8, theparts of the coaster brake and planetary gearing are similar to thestructure first described, and are similarly numbered. In thisembodiment, however, the sun gear 58 is formed as an elongated gearjournalled on an adjustable bearing member 60. A spider 59 is splined onthe sun gear and carries a plurality of key members in the form of pins6| adapted to engage alternatively in openings 62 in an anchor member63, or in openings 64 in the planet carrier 4. The spider 59' isnormally maintained in the high gear position as illustrated in Fig. 7

ing against the spider and in a thrust ring 10 mounted on the end of sungear 58. Means for moving the spider longitudinally to disengage thepins 6| from planet carrier 4 and engage them with the anchor member 63are provided in the form of a shifter ring 66 journaled on the peripheryof the spider and provided with radial lugs 61 arranged to traverselongitudinal slots 68 in a cup member 69 fixed in any suitable way tothe anchor member 63. Manually operable means for moving the ring 66longitudinally is provided in the form of a rotatable sleeve 1|journalled on the periphery of the cup member 69 and having inclinedslots 12 adapted to receive the ends of the lugs 61 of the shifter ring66. Rotation of the sleeve 1| by the operator to adjust the shifter ringis eifected by an arm 13 which is actuated preferably by the same formof snap-action shifting means illustrated in Fig. 6.

In this embodiment of the invention, the bearing sleeve 60 is adjustedby means of a disc 14 in unison whereby the hub is driven at the samespeed as the sprocket l1. Operation of the shifting mechanism by therider of the vehicle to rotate the sleeve H and thus move the spider 59to cause the pins 6| to engage in the openings 62 in the anchor member63, causes the sun gear to be prevented from rotation whereby the planetcarrier 4 and the hub are caused to rotate at a reduced speed from thesprocket I1.

It will be understood that in both embodiments of the inventionarresting the rotation of the sprocket I 1 causes the parts of thecoaster brake to move into coasting position whereby the hub I iSipermitted to rotate freely, and backward rotation of the sprocket I!causes application of the brake in the usual and well-known manner.

Although certain embodiment of the invention have been shown anddescribed in detail, it will be understood that other embodiments arepossible and various changes may be made in the design and arrangementof the parts without departing from thespirit of the invention asdedefined in the claims appended hereto.

What is claimed is? 1. In a variable speed transmission for velocipedesand the like, a driving orbit gear, a driven planet carrier, a sun gear,planet gears on the carrier meshing with the orbit and sun gears, ananchor member, a key member rotatably mounted on the sun gear, andmanually operable means for tilting said key member to cause it toengage the planet carrier or the anchor member alternatively.

2. In a variable speed transmission for velocipedes and the like, adriving orbit gear, a driven planet carrier, a sun gear, planet gears onthe carrier meshing with the orbit and sun gears, an anchor member, abifurcated key pivotally mounted on the sun gear, and manually operablemeans for tilting said key to alternatively engage it with the planetcarrier or the anchor member.

3. In a variable speed transmission for velocipedes and the like, adriving orbit gear, a driven planet carrier, a sun gear, planet gears onthe carrier meshing with the orbit and sun gears, an anchor member, abifurcated key pivotally mounted on the sun gear, and means for tiltingthe key into engagement with the planet carrier or the anchor memberincluding a nonrotatable member having a rib engaging between thefurcations of the key, and a manually operable rotatable member havingan inclined connection with the non-rotatable member.

4. In a velocipede or the like, a hub, an operating member thereforjournalled therein, an axle journalled in the hub, driving means for theoperating member including a sprocket and orbit gear member, planetgears meshing therein journalled on the operating member and a sun gearmeshing with the planet gears, a bearing member for the axle in theoperating member adjustably mounted on the axle and forming a journalfor the sun gear, and anchor member journalled on the bearing member,means for holding the anchor member stationary while permitting rotaryadjustment of the bearing member on the axle, and keying means rotatablewith the sun gear but movable with respect thereto to alternativelyengage the operating member or the anchor member.

5. In a velocipede or the like, a hub, an operating member thereforjournalled therein, an

axle journalled. in the hub, driving means for the operating memberincluding a sprocket and orbit gear member, planet gears meshing thereinjournalled on the operating member and a sun gear meshing with theplanet gears, a bearing member adjustably mounted on the axle rotatablysupporting the sun gear, an anchor member mounted on the bearing member,means for adjustably confining the sun gear and anchor member on thebear member, means for locking the bearing member in adjusted position,and manually operable keying means for optionally locking the sun gearto the operating member or the anchor member.

6. In variable speed gearing for velocipedes or the like, a drivingorbit gear member, a driven planet carrier, a controlling sun gear, ananchor member, keying means pivotally connected to the sun gear, anon-rotatable ring member engaging the keying means and movable to shiftsaid. means alternatively into engagement with the planet carrier or theanchor member, and a manually operable rotatable sleeve having aninclined connection with said ring.

7. In a velocipede or the like, a hub, an operating member thereforjournalled therein, an axlejournalled in the hub, and driving means forthe operating member including a sprocket member, planetary reductiongearing comprising a sun gear, a stationary bearing member for the sungear adjustalbly mounted on the axle, an anchor member journalled on thebearing member, a torque arm holding the anchor member stationary whilepermitting rotary adjustment of the bearing member on the axle, a keyingmember non-rotatably mounted on the sun gear and having keys movableinto engagement with either the operating member or the anchor member,and manually operable means for shifting said keys.

8. In a velocipede or the like, a hub, an operating member thereforjournalled therein, an axle journalled in the hub, and driving means forthe operating member including a sprocket member, planetary reductiongearing comprising a sun gear, a stationary bearing member for the sungear adjustably mounted on the axle, an anchor member'on the bearingmember, a keying member splined on the sun gear and having keys movableinto engagement with either the operating member or anchor member, andmanually operable means for shifting said keying member longitudinally.

9. In a velocipede or the like, a hub, an operating member journalledtherein, an axle journalled in the operating member, driving means forthe operating member including a sprocket member, planetary reductiongearing comprising a sun gear, means rotatably mounting the sun gear onthe axle, an anchor member, said operating member and anchor memberhaving oppositely arranged openings, and keying means nonrotatablyconnected to the sun gear and shiftable to engage either the openings inthe operating member or those in the anchor member, and snap actionshifting means for the keying means including a lever, a spring linkoperatively connected thereto, and manually operable means forcompressing the spring link and moving it beyond dead center withrespect to said lever so that expansion of the link moves the lever toshift the keying means.

FLOYD J. SWEET.

